Who came after Abraham in the line of the covenant nation?
Following Abraham in the covenant line was Isaac, then Jacob, and then Jacob's twelve sons. These twelve sons became the twelve tribes of Israel, who eventually went into Egypt and were later led out by Moses and into the land by Joshua.
Les explains that after Abraham received the covenant promise that a nation would come from him, the next person in response to that covenant promise was Isaac. The next in response was Jacob, and out of Jacob came the twelve sons. One of those sons was Joseph. Because of Joseph and the grain, those twelve sons ended up down in Egypt. While there, their families exploded in population, and those twelve sons became the twelve tribes of Israel. Moses later led them out through the wilderness, and Joshua led them into the land.